Method and device for detecting a power-changing manipulation of an internal combustion engine

A method for detecting a power-changing manipulation of an internal combustion engine, wherein the internal combustion engine has an intake tract and a pressure sensor which is arranged in the intake tract, wherein the method comprises the following steps:

• acquiring a signal profile over a specific time period by means of the pressure sensor, wherein periodically repeating acquired signal profile sections which are characteristic of periodically repeating pressure changes in the intake tract are ascertained from the acquired signal profile,
• providing a modelled signal profile over the specific time period, from which periodically repeating modelled signal profile sections which are characteristic of expected periodically repeating pressure changes in the intake tract are ascertained,
• comparing a signal portion of an acquired signal profile section, which is characteristic of the pressure change in the intake tract in a period of the acquired signal profile, with the corresponding signal portion of the corresponding modelled signal profile section, which is characteristic of the expected pressure change in the intake tract during the same period, in order to detect the power-changing manipulation, and
• detecting the power-changing manipulation based on a time delay in the acquired signal profile in relation to the modelled signal profile, wherein the time delay is caused by the power-changing manipulation,
• wherein measurement signals from the pressure sensor are manipulated by a power-changing manipulation device so that the control unit causes the internal combustion engine to operate at a power level higher than a predetermined operating range of the internal combustion engine.